Toilet systems have been developed for aircraft which use an air pressure differential to move waste from the toilets to a waste holding tank. During the flushing cycle, waste and flushing liquid mix with air as they travel to the waste holding tank. As the air, waste and flushing liquid enter the holding tank, air present within the holding tank passes from the tank through a vent outlet in the tank wall. In most instances, the air leaving the holding tank is vented overboard of the aircraft to the atmosphere. It is necessary that the air thus vented be free of liquid, foam and mist for both sanitary and aesthetic reasons. In order to accomplish this, these tanks have liquid/gas separators which separate the gases from the liquid and vent these gases overboard.
When the waste tanks become full, a sensor located inside the tank generates a signal which automatically shuts the tank off. However, waste liquid can leave a coating on these sensors causing them to generate a false signal indicating the tank is full when in fact it may be empty. This results in an inoperative toilet system. On passenger aircraft, such a failure can lead to vocal passenger dissatisfaction.
Conventionally, a number of deflectors for liquid level response devices have been disclosed. For example, U.S. Pat. No. 1,112,533 by Griffiths describes a compound lever ball-cock for a toilet in which a water deflection hood is included. In addition, various vacuum toilet systems have been disclosed including the system described in U.S. Pat. No. 4,521,925 by Chen et al, and assigned to the assignee of this application. Furthermore, U.S. Pat. No. 4,385,912 by Parrick et al, also assigned to the assignee of this application, describes a liquid/gas separator for a waste holding tank installed in an aircraft.